Compliance mechanism

ABSTRACT

A compliance mechanism ( 10 ) is disclosed for maintaining a fluid applicator ( 47 ) in contact with the surface of object ( 71 ) for fluid application. The compliance mechanism includes an L-shaped bracket ( 15 ) having a first leg ( 17 ) and a second leg ( 19 ), each leg having a tab. A first dual acting fluid operated cylinder ( 32 ) is slidably positioned on the first leg ( 17 ) of the L-shaped bracket ( 15 ). First cylinder ( 32 ) has a piston rod that advances during fluid actuation of the first cylinder. A second dual acting fluid operated cylinder ( 35 ) is slidably positioned on the second leg ( 19 ) of the L-shaped bracket ( 15 ). The second cylinder ( 35 ) has piston rod that advances during fluid actuation of the second cylinder ( 35 ). A fluid applicator ( 47 ) is on first cylinder ( 32 ) for applying fluid to object ( 71 ). The first cylinder ( 32 ) allows fluid applicator ( 47 ) to move relative to the object in a second direction whereby fluid applicator ( 47 ) is maintained in contact with object ( 71 ) during fluid application.

This application is a 371 of PCT/US99/22950 field Oct. 12,1999 whichclaims the benefit of Provisional application No. 60/104,259 filed onOct. 14, 1998.

FIELD OF THE INVENTION

The present invention is directed to a compliance mechanism that is usedto maintain a fluid applicator in contact with the surface of an objectto which a fluid is being applied. More particularly, the compliancemechanism is constructed so that the fluid applicator will remain incontact with the surface of the object during relative movement betweenthe object and the fluid applicator. In addition, the compliancemechanism allows the fluid applicator to accommodate changes in theshape of the object without losing contact with the object during thefluid application process.

One of the primary applications of the compliance mechanism is theautomotive glass industry where the fluid applicator is used to applyvarious fluids to the edge of the windshield, lights, and back window.The compliance mechanism will be generally described with regard to thisparticular automotive application. However, it should be understood thatthis invention is also suitable for a wide range of other fluidapplications. The automotive glass application is only one use and isnot meant to limit the scope of the applications for the invention.

DESCRIPTION OF THE PRIOR ART

The invention is particularly adapted for the production of glazingunits or window assemblies for automotive vehicles, although it willfind utility generally in a great many other fields. Installation offixed window units in earlier automotive vehicles generally involvedmanual installation of the glazing unit using suitable mechanicalfasteners such as metal clips for securing the unit in the vehicle body,applying sealant around the marginal edges of the glazing unit, andpositioning decorative trip strips around the unit to cover the junctionbetween the marginal edges of the glazing unit and the adjacent portionsof the vehicle body. Assembly and installation of such units wasrelatively slow and costly inasmuch as a considerable amount of laborwas required. The procedure was not readily adaptable to being speededup to accommodate increased automobile production line rates, nor was itadapted to being automated.

Efforts to overcome these disadvantages resulted in numerous improvedwindow structures. Thus, unitary window assemblies were developedwherein a sheet of glass was provided with an adjacent peripheral frame,with a gasket of molded material extending between the frame and theperipheral margin of the window to hold the glass sheet within theframe. Fasteners provided at spaced locations along the frame permittedthe entire assembly to be guided into position over an appropriateopening in a vehicle and secured to the vehicle as a unit. Such unitarywindow units reduce the time required and simplify installation in thevehicle opening. However, due to the labor required in manuallyassembling the frame and gasket on the sheet of glass, the structuresare relatively costly.

More recently, in order to eliminate the manual assembly, so-calledencapsulated grazing units have been developed wherein individual sheetsof glass or laminated glass units are formed with integral frame orgasket members molded and cured in situ by a reaction injection molding(RIM) process. One such process and resulting product is shown anddescribed in U.S. Pat. No. 4,561,625 to Weaver. Such encapsulatingglazing units can be fabricated with a minimum of hand labor, and theresulting units can be readily attached to the portions of the vehiclebody defining the window openings during assembly of the vehicle.

As described in the aforementioned patent, such encapsulated units arefabricated by disposing a predetermined portion of the marginalperiphery of a sheet of transparent material within a mold structure. Apolymeric gasket forming material is injected into the mold cavity andcured in situ on the sheet to encapsulate the marginal peripheral edgeportion of the sheet. The resulting assembly can then be readilyattached to the body portion defining the periphery of a window openingduring manufacture and assembly of a vehicle.

Due to the nature of the glass surfaces, it is known that the gasketmaterials may not form a permanent, long term bond directly to theglass. Thus, they may not maintain adhesion to the glass surface for alength of time consistent with the life of the automobile. Exposure toweather moisture and sunlight, as well as other factors, may cause thegasket material to loosen from the glass with the passage of time, andultimately to separate entirely from the glass. In order to improve theadherence of the gasket material to the glass and increase the servicelife of the encapsulated units to an acceptable level, it has beencommon practice to apply a coating of a liquid primer material to theaffected surface of the glass prior to formation of the gasket thereon.Heretofore, this has been accomplished as by manually painting a band ofthe primer material along the appropriate edge portion of the glasspanel. Such a procedure may, for example, utilize a brush periodicallydipped in a container of the primer material, or a plastic squeezebottle containing the primer material and having a suitable dispensingtip. In any event, the procedures are not entirely satisfactory in thatthey are time-consuming, labor-intensive and may not result in asatisfactory coating of the primer material. Thus the primer layer,which is generally a urethane material, should be applied as a uniform,continuous, relatively thin band in order to function properly. Shouldthe layer be of excessive thickness, it may separate within the layeralong a cleavage plane, resulting in failure of the bond. Of course, ifthe layer is not of sufficient thickness or if certain areas are notcoated, the primer layer would likewise be ineffective for its intendedpurpose. The primer, and particularly the solvent therefore, may betoxic in nature so that manual application thereof, particularly whenusing an open container of the primer, may require use of protectiveequipment by the workers. Such manual application processes alsogenerally result in waste of the primer material and generally messyconditions in the work place. Due to the difficulty in controlling thewidth of manually applied bands, it may also be necessary to mask thework piece prior to application of the primer material.

The term “compliance” has been applied to the interface between a tooland the product that the tool is designed to act upon. A programmedrobot or other motion device can be used to define a travel path thatcoincides with the perimeter or across a product. One primaryapplication involves the deposition of primers, paint, and activators,adhesives, etc. to aid in the attachment of foam tapes, plasticmoldings, metal components such as hinges, locks and all types ofencapsulated products. In the process of applying a liquid primer to adefined surface it is desirable to have resiliency between the primerdepositing pad or brush and the coated product. The soft touch andfeather-like contact (resembling the fine touch of an artist) is theideal result to give the designed coverage, exact line demarcation andlong applicator life. The invention has the capability of being mountedon the robot arm, the arm of a work station module or on a stationarygantry type device that moves the product to be coated to give thedesired coverage. The compliance unit of this design, provides thetracking resilience that is required in many robotic applications. Suchtracking is virtually impossible to achieve with a robot because of thevariable curvatures of the products and the almost impossibility ofprogramming a robot to exacting dimensions on a non-uniform product.

Attempts have been made to automate the application of the primermaterial to the edge of a glass surface. U.S. Pat. No. 5,131,349 showsone method for automating the application of the primer material.However, the glass surfaces, especially in automotive applications,frequently change in contour and shape, and it is difficult to maintainthe fluid applicator described in the '349 patent in contact with theglass surfaces. It is also difficult to maintain a very light contactpressure between the fluid applicator and the glass surfaces so that adesired thickness of primer is uniformly applied.

Thus, there is a need in the industry for a compliance mechanism thatcan maintain contact with a surface that changes in contour and shape.There is also a need for a compliance mechanism that maintains a lightcontact pressure with the surface of the object that is to be primed orcoated. There is also a need in the industry for a compliance mechanismthat can apply a primer or coating at a desired thickness in a uniformmanner.

SUMMARY OF THE INVENTION

This invention consists of a compliance device that is used to apply aliquid to a product, primarily glass, in a precision lay down pattern,utilizing specialized and unique flow applicator tips. Some of the 20applicator tip designs have been documented in U.S. Pat. No. 5,131,349.

In the process to apply primers, adhesives, promoters, etc. toautomotive glass and like application, it is necessary to maneuver thespecialized tip applicators into many angular modes to provide constantregulated pressure contract with the glass. It is also necessary tomaintain band width coverage on all designated surfaces and at the sametime control the mill thickness of the fluid that is applied to meet therequired quality standards.

There are many applications where the design of the product demands anon-uniform and constant changing band width on one or two edges or onone or both sides of the light and/or a mixture of these variables on asingle piece of glass. To accomplish such requirements, it is frequentlynecessary to employ two different applicator tip designs. On one portionof the product, it may be necessary to have a vertical placement of theapplicator tip with respect to the product. On another section of theproduct, it may be necessary to use the applicator tip in a horizontalmode. Many design factors of the product dictate the ability orinability to perform the required liquid lay down in one cycle.

The capability to perform this type of complex pattern for liquid laydown in a rapid, single automatic cycle has been accomplished with thedesign of the compliance mechanism that can rotate within its mountingto position the fluid dispenser in either a vertical or horizontalposition or an angular position between vertical and horizontal.

A compliance mechanism is disclosed for maintaining a fluid applicatorin contact with the surface of an object to which a fluid is beingapplied. The compliance mechanism includes an L-shaped bracket having afirst leg and a second leg. A first tab is positioned at the end of thefirst leg and a second tab positioned at the end of the second leg. Afirst dual acting fluid operated cylinder is slidably positioned on thefirst leg of the L-shaped bracket. The first cylinder has a piston rodthat extends from the first cylinder and the fluid actuation of thecylinder causes the piston rod to be advanced relative to the firstcylinder. The end of the piston rod that extends from the first cylinderis secured to the first tab. A second dual acting fluid operatedcylinder is slidably positioned on the second leg of the L-shapedbracket. The second cylinder has a piston rod that extends from thesecond cylinder and the fluid actuation of the cylinder causes thepiston rod to be advanced relative to the second cylinder. The end ofthe piston rod that extends from the second cylinder is secured to thesecond tab. A fluid applicator is positioned on the first cylinder forapplying a fluid to the object. The first cylinder allows the fluidapplicator to move relative to the object in first direction and thesecond cylinder allowing the fluid applicator to move relative to theobject in a second direction whereby the fluid applicator is maintainedin contact with the object during the application of the fluid to theobject.

It must be pointed out that the compliance mechanism and the associatefluid dispenser and applicator tip can be mounted on the end of a robotarm to apply a fluid by advancing the applicator tip with the robot armover the stationery glass product. It is also possible to move the glassproduct relative to the applicator tip during the fluid applicationprocess.

Other objects and advantages of the present invention will becomeapparent to those skilled in the art upon a review of the followingdetailed description of the preferred embodiments and the accompanyingdrawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a side elevation view of the compliance mechanism of theinvention.

FIG. 2 is a side elevation view of the compliance mechanism of theinvention.

FIG. 3 is a side elevation view of the compliance mechanism of theinvention.

FIG. 4 is a side elevation view of the compliance mechanism of theinvention.

FIG. 5 is a side elevation view of the compliance mechanism of theinvention.

FIG. 6 is a side elevation view of the compliance mechanism of theinvention.

FIG. 7 is a side elevation view of the compliance mechanism of theinvention.

FIG. 8 is a side elevation view of another feature of the compliancemechanism invention.

FIG. 9 is a side elevation view of another feature of the invention.

FIG. 10 is a plan view of another feature of the invention.

FIG. 11 is a side elevation view of the embodiment of FIG. 10.

FIG. 12 is a perspective view of another feature of the compliancemechanism,

FIG. 13 is a side elevational view of the compliance mechanism shown inFIG. 12.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT(S)

The invention relates to a compliance mechanism that can be utilized toapply a fluid layer to an object. More particularly, the compliancemechanism has the ability to accommodate motion in two directions andhas a very light touch. The features of the invention will be morereadily understood by referring to the attached drawings in combinationwith the following description of the invention.

The compliance mechanism 10 shown in FIGS. 1-7 has an L-shaped bracket15 having a first leg 17 and a second leg 19. The first and second legs17 and 19 are positioned substantially perpendicular to one another. Afirst reinforcing member 21 is secured to the first leg 17 and to aportion 22 of the second leg 19 which is adjacent to the first leg 17.The first reinforcing member 21 provides additional support and rigidityfor the first leg 17. A second reinforcing member 25 is secured to thesecond leg 19 and provides additional rigidity and support for thesecond leg 19. A first slide mechanism 29, such as a linear ball,bearing is positioned on the first leg 17 on the side of the leg that isopposite to the first reinforcing member 21. A second slide mechanism 30is positioned on the second leg 19 on the side that is opposite thesecond reinforcing member 25. A first fluid operated cylinder 32 issecured to the first slide mechanism 29 on the first leg 17. A secondfluid operated cylinder 35 is secured to the second slide mechanism 30positioned on the second leg 19. The first and second fluid operatedcylinders 32 and 35 are dual acting cylinders with fluid supply ports 37located at each end of the cylinders. In practice, it has been foundpreferable to use low friction fluid operated cylinders for thecompliance mechanism. In particular, glass lined low friction fluidoperated cylinders have been found to work particularly well. However,other types of low friction cylinders can also be utilized. The fluidsupply ports 37 are disposed for supplying fluid to either side of thepiston (not shown) located in the interior of the cylinders. A pistonrod 39 is connected to each piston and extends from a first end of thecylinders. The piston rod 39 of the first fluid operated cylinder 32 issecured to a first bracket 41 that extends from the first leg 17 in adirection substantially perpendicular to the first leg 17. The firstbracket 41 extends from the side of the first leg 17 that is opposite tothe first reinforcing member 21. The first bracket 41 is also disposedto be substantially parallel to the second leg 19. The piston rod 39 forthe second fluid operated cylinder 35 is secured to a second bracket 43that extends from the second leg 19. The second bracket 43 extends fromthe second leg 19 in a direction that is substantially perpendicular tothe second leg 19. The second bracket 43 extends from the side of thesecond leg 19 that is opposite to the second reinforcing member 25. Thesecond bracket 43 is disposed to be substantially parallel to the firstleg 17. A protective cover or shield (not shown) can be positioned overthe first and second fluid operated cylinders 32, 35 and the rods forthese cylinders. The cover or shield is designed to protect thecylinders from the operating environment for the compliance mechanism.

As shown in FIG. 7, the first and second fluid operated cylinders 32, 35are supplied with fluid to actuate the cylinders through supply lines44. Each supply line 44 is connected to a at least one self-exhaustingregulator 46. The supply lines 44 extend from the regulators 46 and areconnected to one of the fluid supply ports 37 on the first and secondfluid operated cylinders 32 and 35. The regulators 46 act to reducepressure build up in the first and second fluid operated cylinders 32and 35 so that the force necessary to advance the piston rod 39 in thecylinders does not change over the distance of travel for the rod. Anexample of a self-exhausting regulator 46 that can be used is the SeriesVEX1 regulators sold by SMC Corp.

A fluid dispenser 47 having a fluid applicator tip 49 is secured to thefirst fluid operated cylinder 32. An example of a fluid dispenser thatcan be used is the Model 5000 fluid dispenser sold by Designetics. Thefluid dispenser 47 is positioned on the first fluid operated cylinder 32so that the fluid applicator tip 49 extends beyond a second end of thefirst fluid operated cylinder 32. The fluid applicator tip 49 usuallyextends beyond the second end of the first fluid operated cylinder 32that is opposite to the first end where the piston rod 39 extends fromthe cylinder 32. The fluid applicator tip 49 is constructed to have aguide flange 50 that engages an edge of the object 71 that is to becoated with fluid to position the fluid applicator tip 49 with respectto the object 71. The fluid applicator tip 49 usually contacts at leastone other surface of the object. The applicator tip 49 usually has afell or foam pad that applies the fluid to the object that is to becoated. The applicator tip 49 applied fluid to the object in a mannerwell known in this field. Examples of applicator tips 49 that can beused with this invention are Part Numbers Series 11 through Series 67sold by Designetics.

In some applications the applicator tip 49 may not have guide flange 50to position the applicator tip with respect to the object 71. In thissituation, the applicator tip 49 will have to be placed very preciselywith respect to the object 71 so that the fluid layer is applied to thedesired area. Since the applicator tip 49 only engages one surface ofthe object, the compliance mechanism 10 will only be able to effectivelyaccommodate relative movement between the applicator tip 49 and theobject 71 in one direction. In this application, it is only necessary tohave the fluid operated cylinder that controls motion in the oneselected direction be operational. Usually, the fluid operated cylinderthat does not control motion in the desired direction would beeffectively locked to prevent motion in a direction that is notcontrolled by the position of the applicator tip 49.

The second fluid operated cylinder 35 is secured to a bar 53. A flange55 is secured to and extends from the bar 53. The end of the flange 55that is spaced apart from the bar 53 is disposed at an angle withrespect to the bar 53 and a positioning plate 57 is secured to this endof the flange 55. The positioning plate 57 is also disposed at an anglewith respect to the bar 53. The positioning plate 57 is releasablysecured to a positioning member 59 that is connected to a support arm61. The positioning member 59 is disposed at the same angle with respectto the support arm 61 that the positioning plate 57 is disposed at withrespect to the flange 55. A releasable securing means 63 such as a bolt65 and a nut 67 is used to releasably secure the positioning plate 57 tothe positioning member 59. In practice, it has been found to bepreferable that the positioning member 59 and positioning plate 57 bedisposed at a 45° angle.

FIGS. 1-3 show the compliance mechanism 10 with the fluid dispenserpositioned in a vertical orientation. FIGS. 4-6 show the compliancemechanism 10 with the fluid dispenser positioned in a horizontalorientation. It should be understood that the fluid dispenser will worksatisfactorily in either orientation or in any position between thesetwo orientations.

In operation, the compliance mechanism 10 is utilized to place a fluidlayer or strip on an object that is positioned adjacent the compliancemechanism. Usually, the object is moved with respect to the compliancemechanism during the fluid application process. However, it is alsopossible for the compliance mechanism to be moved relative to the objectduring the coating process.

To begin the coating process, the compliance mechanism 10 is positionedin the configuration shown in FIG. 1 which is a biased position for thecompliance mechanism. In the position shown in FIG. 1, the first fluidoperated cylinder 32 is positioned at the end of the length of strokefor the cylinders and the second fluid operated cylinder 35 ispositioned in the fully retracted position for the cylinder. This placesthe applicator tip 49 at a location that is spaced apart from thesupport arm 61 and allows the first and second fluid operated cylindersto utilize their full range of motion when engaging an object forcoating. This is accomplished by supplying fluid to the fluid supplyports 37 on each side of the piston (not shown) located in the cylinder32 so that the piston 39 is advanced to substantially its fully extendedposition for the first cylinder and the piston is advanced to its fullyretracted position for the second cylinder. The first and second fluidoperated cylinders 32 and 35 are low friction cylinders and only a verysmall force is required to operate or move the piston in the cylinders.The piston rod 39 that is connected to the piston in the first fluidoperated cylinder 32 is connected to the first tab 41 that extends fromthe first leg 17. As the piston is advanced in the first fluid operatedcylinder 32, the piston rod 39 will be caused to extend or retract intothe first fluid operated cylinder 32 by the movement of the piston.Since the piston rod 39 is connected to the first tab 41, this causesthe first fluid operated cylinder 32 to be advanced with respect to thefirst leg 17. Since the first fluid operated cylinder 32 is mounted onthe slide mechanism 29 that has very little resistance to movement, itis very easy to advance the first fluid operated cylinder with respectto the first leg 17. The second fluid operated cylinder 35 is suppliedwith fluid through the fluid supply ports 37 in the manner justdescribed for the first fluid operated cylinder 32 and as describedabove, it only requires a very small force to advance the piston (notshown).

Once the first fluid operated cylinder 32 and the second fluid operatedcylinder 35 are positioned as shown in FIG. 1, the weight of the fluiddispenser 47 and the fluid pressure for the fluid supplied to the fluidsupply ports 37 will essentially control the resistance to movement forthe first and second fluid operated cylinders. When the object 71 ispositioned in contact with the fluid applicator tip 49 on the fluiddispenser 47, it is desirable to maintain the fluid applicator tip incontact with the object during the application process. In mostapplications, the object 71 has a change of shape, contour or there areirregularities in the object 71 that it is necessary for the fluidapplicator tip 49 to move in both a horizontal and vertical direction tomaintain contact with the object 71.

The fluid applicator can be supplied with a fluid supply system such asdescribed in U.S. Pat. No. 5,131,349. The description of this fluidsupply system described in U.S. Pat. No. 5,131,349 is herebyincorporated by reference into this patent application. However, itshould be understood that other fluid supply systems could also beutilized with the present invention.

When the coating operation begins, the object 71 is brought intoposition adjacent the fluid applicator tip 49. The compliance mechanismwill be brought into the position shown in FIG. 1 to be prepared to beengaged by the object. The object is then moved to engage the applicatortip 49. The object 71 causes the applicator tip 49 and fluid dispenser47 to move to substantially the position shown in FIG. 2. This is thecentral or neutral position for the first and second fluid operatedcylinders 32, 35. From the position shown in FIG. 2, the fluidapplicator tip 49 can be advanced or retracted in two directions arelatively equal amount to accommodate changes presented by the object71 during the fluid application process. The fluid supplied to the fluidsupply ports 37 on the first and second fluid operated cylinder 32, 35are balanced in a way so there is a slight bias on the cylinders in thedirection toward the object 71. The amount of the bias can be controlledby the pressure differential of the fluid supplied to either side of thepiston in the first fluid operated cylinder 32 and second fluid operatedcylinder 35. The self-exhausting regulators 46 substantially eliminatepressure build-up in the first and second fluid operated cylinders 32,35 during the operation of the cylinders. The regulators 46 assist inhaving the biasing, force maintained at substantially the desired levelas the first and second fluid operated cylinders 32, 35 are caused tomove during the operation of the compliance mechanism 10. In mostapplications, the biasing pressure differential is relatively smallsince a light biasing force is all that is necessary to properlyposition the fluid applicator tip. Also, it is important that thebiasing force created by the pressure differential does not undulyrestrict the ability of the first fluid operated cylinder 32 to movewith respect to the object 71. The biasing force in the first and secondcylinder can be set at different levels to accommodate particularprocessing parameters.

In practice, it has been found that a biasing force of from about one(1) ounces per square inch to about twenty five (25) ounces per squareinch on the applicator tip 49 works well in keeping the applicator tip49 in contact with the object that is being coated. It has been foundespecially preferable to utilize a biasing force from about four (4)ounces per square inch to about twelve (12) ounces per square inch tokeep the applicator tip 49 in contact with the object that is beingcoated. This low biasing force creates a feather light touch that allowsthe applicator tip to work most effectively. The light contact betweenthe applicator tip 49 and the object also prolongs the life to theapplicator tip. However, it should be understood that the biasing forcecan vary from the above ranges for particular uses of the compliancemechanism. In the example of applying a coating fluid to an object, thenature of the object and the fluid that is being applied to the objectwill have a significant impact on establishing the biasing forces forthe first and second fluid operated cylinders.

However, it should be appreciated that the fluid supplied to the firstor second fluid operated cylinders 32, 35 can be increased to a levelthat will effectively lock the cylinder and prevent movement of thecylinder and the compliance mechanism in one or both directions. Thereare applications where it is desirable to lock the compliance mechanismin this manner to achieve a desired coating operation on a particularobject. As an example, if the applicator tip 49 does not have an edgeguide 50, it may be desirable to lock one of the cylinders to maintainthe proper location for the applicator tip relative to the object. Thecylinders can be locked during the entire coating operation or justduring a portion of the overall coating operation.

When the object 71 is being coated by the fluid applicator tip 49, anymovement away from the fluid applicator tip 49 in a vertical directionwill result in the first fluid operated cylinder 32 moving toward theobject 71 due to the biasing force in the first fluid operated cylinder.If the object 71 moves in a vertical direction toward the fluidapplicator tip 49, the first fluid operated cylinder 32 will move in thesame direction as the object 71 and keep the fluid applicator tip 49 incontact with the surface of the object 71. Since the biasing force inthe first fluid operated cylinder 32 is relatively small, only a smallamount of pressure is necessary to cause the fluid dispenser 47 and thefirst fluid operated cylinder 32 to move in response to the change inposition of the object 71. The small biasing force in the first fluidoperated cylinder 32 results in a very light touch or feel for theapplicator tip 49 on the object 71. Since the first fluid operatedcylinder 32 is a low friction cylinder and is mounted on the slidemechanism 29, there is almost no resistance to movement of the firstfluid operated cylinder 32 other than the biasing force in thiscylinder.

If the object 71 moves away from the second fluid operated cylinder 35,the biasing force in this cylinder will cause the second fluid operatedcylinder 35 to move toward the object and keep the applicator tip 49 incontact with the object 71. If the object 71 moves in a direction towardthe second fluid operated cylinder 35, it is only necessary to overcomethe biasing force in this cylinder to cause the second fluid operatedcylinder 35 to move with the object 71 and maintain the fluid applicatortip 49 in the desired position with respect to the object.

FIG. 1 and FIG. 3 show the range of motion for the fluid dispenser 47 invertical and horizontal direction. In practice, it has been found thatthis range of motion is satisfactory to accommodate most objects 71 onwhich a fluid is applied.

In some applications, it may be necessary to have a stronger biasingforce in the first fluid operated cylinder 32 and the second fluidoperated cylinder 35 to maintain proper positioning for the fluiddispenser 47 to achieve the desired application of the fluid. If higherpressures are required, it is only necessary to adjust the fluidpressures in the first and second fluid operated cylinders 32, 35 toincrease the resistance of movement in the cylinders and achieve thedesired fluid applicator tip pressure on the object 71.

It is frequently necessary to change the angular position of the fluiddispenser 47 to apply a fluid in a desired manner to an object 71. Tochange the positioning of the fluid dispenser 47, it is only necessaryto loosen the releasable securing means 63 and change the orientation ofthe positioning plate 57 with respect to the positioning member 59. Asshown in FIGS. 4, 5 and 6, the positioning plate 57 has been rotatedrelative to the positioning member 59 so that the fluid dispenser 47 isnow disposed in a horizontal orientation instead of the verticalorientation shown in FIGS. 1, 2 and 3. It is possible to locate thefluid dispenser 47 in other positions between the positions shown inFIGS. 1, 2 and 3 and the positions shown in FIGS. 4, 5 and 6. Once thedesired position is obtained for the fluid dispenser 47, the releasablesecuring means 63 is tightened to maintain the positioning plate 57 inthe desired position with respect to the positioning member 59.

The compliance mechanism as shown in FIG. 7 can be utilized on anautomated system for applying fluid to an object. In this application,the compliance mechanism 10, fluid dispenser 47 and fluid applicator tip49 are positioned on the arm 61. The arm 61 can be movable and be usedto move the fluid dispenser 47 into position so that it is adjacent theobject 71 on which the fluid is to be applied. The object 71 can bemoved to the desired position for fluid application by the use of arobot 13 or other suitable positioning means. The robot 13 can be usedto advance or rotate the object 71 with respect to the applicator tip 49during the application of the fluid to the object.

As shown in FIG. 8, it is also possible to use one or more rotaryactuators 69 to position the fluid dispenser 47 and fluid applicator tip49 in the desired position. The rotary actuator 69 replaces thepositioning member 59 previously described as a mechanism for angularlypositioning the fluid dispenser 47. The rotary actuator 69 usuallycontains a motor or fluid actuated mechanism that rotates the rotaryactuator to the desired position. A control means (not shown) can beused to select the desired position for the rotary actuator 69 and thefirst dispenser 47.

As shown in FIG. 9, the compliance mechanism 10, fluid dispenser 47 andfluid applicator tip 49 are positioned on or connected to a robot 73.The robot 73 is used to position the fluid dispenser 47 and fluidapplicator tip 49 into position adjacent the object 71 on which thefluid is to be applied. The robot 73 can be used to advance theapplicator tip 49 around the areas of the object that are to receive alayer of fluid. In this example, the object 71 is not usually movedduring the application of the fluid layer by the applicator tip 49.

As shown in FIGS. 10 and 11, the compliance mechanism 10 previouslydescribed can also be mounted on a moveable gantry 151 to properlyposition the applicator tip 49 with respect to an object 155 that is tobe coated. The gantry 151 has opposed first guide rails 161 and opposedsecond guide rails 165. The first guide rails 161 are positioned in asubstantially parallel relationship. The second guide rails 165 are alsopositioned in a substantially parallel relationship. The first guiderails 161 are disposed in a substantially perpendicular relationship tothe second guide rails 165. A first driven member 167 is positioned inoperative contact with the first guide rails 161. A suitable drive means175 is connected to at least one of the first guide rails to cause thefirst driven member 167 to be advanced along the first guide rails 161.A second driven member 169 is positioned in operative contact with thesecond guide rails 165. A suitable drive means 177 is connected to atleast one of the second guide rails to cause the second driven member169 to be advanced along the second guide members 165. In mostapplications, the drive means 175 and 177 are substantially the same andact to index the driven members 167 and 169 along their respective guiderails 165 and 167. A mounting bracket 181 is slidably connected to thefirst driven member 167 and the second driven member 169 so that themounting bracket 181 is free to move when said first and second drivenmembers are caused to move by the drive means 175 and 177. As shown inFIG. 11, the compliance mechanism 10 is mounted on a side of themounting bracket 181 that is spaced apart from the first and seconddriven members 167 and 169. By activation of the drive means 175 and177, the first and second driven members 167 and 169 can be indexed oradvanced to position the compliance mechanism 10, the fluid dispenser 47and the applicator tip 49 in a desired location with respect to theobject 155 that is to be coated. By proper operation of the gantry 151,the applicator tip 49 can be advanced around the object 155 until thedesired coating is applied. The compliance mechanism 10, the fluiddispenser 47 and the applicator tip 49 all function in the mannerpreviously described.

The compliance mechanism 200 shown in FIGS. 12 and 13 has an L-shapedbracket 205 having a first leg 207 and a second leg 209. The first andsecond legs 207 and 209 are positioned substantially perpendicular toone another. The first and second legs are formed of a U-shaped channelhaving a base 211 and opposed side walls 213 that extend from the base211. The side walls 213 are usually disposed so they are insubstantially parallel relationship. A first slide mechanism 219 such asa linear ball bearing is secured to the base 211 of the first leg 207. Asecond slide mechanism 220 is secured to the base 211 of the second leg209. A first fluid operated cylinder 222 is secured to the first slidemechanism 219 in the first leg 207. A second fluid operated cylinder 225is positioned on the second slide mechanism 220 positioned in the secondleg 209. The first and second fluid operated cylinders 222 and 225 aredual acting cylinders with supply ports 227 located on each end of thecylinders. The first and second fluid operated cylinders 222 and 225 andthe slide mechanisms 219,220 function as previously described in thispatent application. Slots 231 are positioned in at least one of the sidewalls of the first and second U-shaped legs 207 and 209 to provideaccess to the fluid supply ports 227. A piston rod 229 is connected toeach piston and extends from a first end of each cylinder. The end ofthe piston rod that extends from the cylinder is secured to a plate 235positioned at one end of the first and second legs 207 and 209. A coverplate 241 is secured to the first fluid operated cylinder and the coverplate 241 is designed to close the open side of the first U-shaped leg207. The cover plate 241 is designed so that it can move along the firstleg 207 as the first slide mechanism and first fluid operated cylinderis caused to move within the first leg 207. A fluid dispenser 247 havinga fluid applicator tip 249 is secured to the cover plate 241. The secondcylinder 225 of the compliance mechanism 200 is mounted to appropriatesupport structure as previously described in this patent application. Anopening 245 can be positioned in the base 211 of the second leg 209adjacent the first leg 207 to act as a drain for any undesirablematerial that might accumulate in the second leg 209. In addition, aflexible cover, not shown, can be positioned over the open side of thesecond U-shaped leg 209 to prevent unwanted contaminants fromaccumulating in the second leg. The compliance mechanism 200, shown inFIGS. 12 and 13 functions in substantially the same manner as thepreviously described compliance mechanism 10.

The above detailed description of the present invention is given forexplanatory purposes. It will be apparent to those skilled in the artthat numerous changes and modifications can be made without departingfrom the scope of the invention. Accordingly, the whole of the foregoingdescription is to be construed in an illustrative and not a limitativesense, the scope of the invention being defined solely by the appendedclaims.

We claim:
 1. A compliance mechanism to maintain a fluid applicator incontact with the surface of an object to which a fluid is being appliedcomprising: an L-shaped bracket having a first leg and a second leg; afirst tab positioned at a first end of said first leg and a second tabpositioned at a first end of said second leg; a first dual acting fluidoperated cylinder slidably positioned on said first leg of said L-shapedbracket, said first cylinder having a first piston rod that extends fromsaid first cylinder, said fluid actuation of said cylinder causing saidfirst piston rod to be advanced relative to said first cylinder, saidend of said piston rod that extends from said first cylinder beingsecured to said first tab; a second dual acting fluid operated cylinderslidably positioned on said second leg of said L-shaped bracket, saidsecond cylinder having a second piston rod that extends from said secondcylinder, said fluid actuation of said cylinder causing said secondpiston rod to be advanced relative to said second cylinder, said end ofsaid piston rod that extends from said second cylinder being secured tosaid second tab; and, a fluid applicator positioned on said firstcylinder for applying a fluid to said object, said first cylinderallowing said fluid applicator to move relative to said object in afirst direction and said second cylinder allowing said fluid applicatorto move relative to said object in a second direction whereby said fluidapplicator is maintained in contact with said object during theapplication of said fluid to said object and whereby said fluidapplicator can be advanced or retracted in said first and seconddirections to accommodate any changes in shape or movement of saidobject during the application of said fluid to said object.
 2. Thecompliance mechanism of claim 1 wherein said first and second cylinderscan be biased towards said object by having a pressure differentialpresent in at least one of said cylinders.
 3. The compliance mechanismof claim 2 wherein said pressure differential on said first and secondcylinders can be great enough to effectively prevent said cylinders frommoving.
 4. The compliance mechanism of claim 2 wherein a linear ballbearing is used to position said first and second cylinders on saidfirst and second legs wherein there is very little resistance tomovement of said first and second cylinders.
 5. The compliance mechanismof claim 2 wherein at least one self-exhausting regulator is used tosupply fluid to said first and second cylinders.
 6. The compliancemechanism of claim 2 wherein said first and second cylinders create abiasing force from about one (1) ounces per square inch to about twentyfive (25) ounces per square inch on said fluid applicator.
 7. Thecompliance mechanism of claim 1 wherein said compliance mechanism isoperatively connected to a movable support arm for positioning saidcompliance mechanism relative to said object.
 8. The compliancemechanism of claim 1 wherein said second dual acting cylinder isoperatively connected to a movable support arm for positioning saidcompliance mechanism relative to said object.
 9. The compliancemechanism of claim 8 wherein said second dual acting cylinder isoperatively connected to a positioning plate that is disposed at anangle with respect to said second dual acting cylinder, said positioningplate being releasably secured to a positioning member on said supportarm whereby said positioning plate can be rotated on said positioningmember to change the position of said compliance mechanism with respectto said object to be coated.
 10. The compliance mechanism of claim 9wherein a releasable securing means secures said positioning plate tosaid positioning member.
 11. The compliance mechanism of claim 8 whereinsaid second dual acting cylinder is operatively connected to a rotaryactuator that can be caused to rotate to position said compliancemechanism with respect to said object that is to be coated.
 12. Thecompliance mechanism of claim 8 wherein said second dual acting cylinderis operatively connected to a gantry mechanism, said gantry mechanismbeing designed to position said compliance mechanism in two planes withrespect to said object that is to be coated.
 13. The compliancemechanism of claim 1, including a means for moving said object relativeto said fluid applicator during the application of said fluid to saidobject.
 14. The compliance mechanism of claim 1, wherein a supply ofsaid fluid is applied to said object.
 15. A method of maintaining afluid applicator in contact with the surface of an object to which fluidis being applied comprising: positioning a fluid applicator on a firstdual acting fluid operated cylinder, said first dual acting fluidoperated cylinder being disposed for moving said fluid applicator in afirst direction; positioning said first dual acting fluid operatedcylinder on a bracket; positioning said bracket on a second dual actingfluid operated cylinder, said second dual acting fluid operated cylinderbeing disposed for moving said fluid applicator in a second direction,whereby said first and second dual acting fluid operated cylinders canaccommodate movement of said fluid applicator to maintain said fluidapplicator in contact with said object; advancing and/or retracting saidfluid applicator in said first and said second directions to accommodateany changes in shape or movement of said object during the applicationof said fluid to said object.
 16. The method of claim 15 in which saidfirst and second dual acting fluid operated cylinders are biased towardssaid object by having a pressure differential present in said first andsecond cylinders.
 17. The method of claim 16 in which said first andsecond cylinders create a biasing pressure from about one (1) ounces persquare inch to about twenty five (25) ounces per square inch on saidfluid applicator.
 18. The method of claim 15 in which said first andsecond cylinders are supplied fluid through at least one self-exhaustingregulator.
 19. The method of claim 15 in which said second dual actingfluid operated cylinder is operatively connected to a rotatablemechanism whereby the position of said fluid applicator with respect tosaid object can be changed.
 20. The method of claim 15 wherein a linearball bearing positions said first and second cylinders wherein there isvery little resistance to movement of said first and second cylinders.21. The method of claim 15 in which said second dual acting fluidoperated cylinder is operatively mounted to a movable support arm forpositioning said fluid applicator relative to said object.
 22. Themethod of claim 21 wherein said second dual action cylinder operativelyis connected to a positioning plate that is disposed at an angle withrespect to said second dual acting cylinder, said positioning platebeing releasably secured to a positioning member on said support arm,and rotating said positioning plate on said positioning member to changethe position of said compliance mechanism with respect to said object tobe coated.
 23. The method of claim 22 in which a securing means securessaid positioning plate to said positioning member.
 24. The method ofclaim 21 in which said compliance mechanism is operatively connected toa gantry mechanism, and positioning said compliance mechanism with saidgantry mechanism in two planes with respect to said object that is to becoated.
 25. The method of claim 15, including moving said objectrelative to said fluid applicator during the application of said fluidto said object.
 26. The method of claim 15, including applying acontinuous supply of said fluid to said object.
 27. A compliancemechanism to maintain a device in contact with the surface of an objectcomprising: a bracket having a first leg and a second leg; a first dualacting fluid operated cylinder slidably positioned on said first leg ofsaid bracket, said first cylinder having a first piston rod that extendsfrom said first cylinder, said fluid actuation of said cylinder causingsaid first piston rod to be advanced relative to said first cylinder;said end of said piston rod that extends from said first cylinder beingsecured to said bracket; a second dual acting fluid operated cylinderslidably positioned on said second leg of said bracket, said secondcylinder having a second piston rod that extends from said secondcylinder, said fluid actuation of said cylinder causing said secondpiston rod to be advanced relative to said second cylinder, said end ofsaid piston rod that extends from said second cylinder being secured tosaid bracket; and, a device positioned on said first cylinder forcontacting said object, said first cylinder allowing said device to movein a first direction and said second cylinder allowing said device tomove in a second direction whereby said first and second fluid operatedcylinders can accommodate movement of said device to maintain saiddevice in contact with said object and whereby said device can beadvanced or retracted in said first and said second directions toaccommodate any changes in shape or movement of said object.
 28. Thecompliance mechanism of claim 27 wherein said first and second cylinderscan be biased towards said object by having a pressure differentialpresent in one of said cylinders.
 29. The compliance mechanism of claim28 wherein a linear ball bearing is used to position said first andsecond cylinders on said first and second legs wherein there is verylittle resistance to movement of said first and second cylinders. 30.The compliance mechanism of claim 27 wherein said first and secondcylinders create a biasing force from about one (1) ounces per squareinch to about twenty five (25) ounces per square inch on said fluidapplicator.
 31. The compliance mechanism of claim 27 wherein at leastone self-exhausting regulator is used to supply fluid to said first andsecond cylinders.
 32. The compliance mechanism of claim 27 wherein saidsecond dual acting cylinder is operatively connected to a movablesupport arm for positioning said compliance mechanism relative to saidobject.
 33. The compliance mechanism of claim 32 wherein said seconddual acting cylinder is operatively connected to a positioning platethat is disposed at an angle with respect to said second dual actingcylinder, said positioning plate being releasably secured to apositioning member on said support arm whereby said positioning platecan be rotated on said positioning member to change the position of saidcompliance mechanism with respect to said object to be coated.
 34. Thecompliance mechanism of claim 33 wherein a releasable securing meanssecures said positioning plate to said positioning member.
 35. Thecompliance mechanism of claim 27, including a means for moving saidobject relative to said device.
 36. A compliance mechanism to maintain adevice in contact with the surface of an object comprising: a brackethaving at least a first leg; a first dual acting fluid operated cylinderslidably positioned on said leg of said bracket, said first cylinderhaving a first piston rod that extends from said first cylinder, saidfluid actuation of said cylinder causing said first piston rod to beadvanced relative to said first cylinder; said end of said piston rodthat extends from said first cylinder being secured to said bracket; adevice positioned on said first cylinder for contacting said object,said first cylinder allowing said device to move in a first directionand in a second direction whereby said first fluid operated cylinder canaccommodate movement of said device to maintain said device in contactwith said object and whereby said device can be advanced or retracted insaid first and said second directions to accommodate any changes inshape or movement of said object.
 37. The compliance mechanism of claim36 wherein said bracket has a first leg and a second leg, said firstfluid operated cylinder being slidably positioned on said first leg. 38.The compliance mechanism of claim 37 wherein a second dual acting fluidoperated cylinder is slidably positioned on said second leg of saidbracket, said second cylinder having a second piston rod that extendsfrom said second cylinder, said fluid actuation of said second cylindercausing said second piston rod to be advanced relative to said secondcylinder, said end of said piston rod that extends from said secondcylinder being secured to said bracket, whereby said second fluidoperated cylinder allows said device to move relative to said object ina second direction.
 39. The compliance mechanism of claim 38 wherein atleast one of said first and second cylinders can be biased towards saidobject by having a pressure differential present in at least one of saidcylinders.
 40. The compliance mechanism of claim 39 wherein at least oneself-exhausting regulator is used to supply fluid to said firstcylinder.
 41. The compliance mechanism of claim 38 wherein a linear ballbearing is used to position said first and second cylinders on saidfirst and second legs wherein there is very little resistance tomovement of said first and second cylinders.
 42. The compliancemechanism of claim 36, including a means for moving said object relativeto said device.